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noun im·pe·tus \ˈim-pə-təs\

Simple Definition of impetus

  • : a force that causes something (such as a process or activity) to be done or to become more active

  • : a force that causes an object to begin moving or to continue to move

Full Definition of impetus

  1. 1 a (1) :  a driving force :  impulse (2) :  incentive, stimulus b :  stimulation or encouragement resulting in increased activity

  2. 2 :  the property possessed by a moving body in virtue of its mass and its motion —used of bodies moving suddenly or violently to indicate the origin and intensity of the motion

Examples of impetus

  1. In a revealing comment, Mr. Updike says an impetus for Rabbit, Run was the “threatening” success of Jack Kerouac's On the Road, the signature book of the 1950s Beat Generation, and its frenetic search for sensation. —Dennis Farney, Wall Street Journal, 16 Sept. 1992

  2. But 1939 gave new impetus to the Western with the Cecil B. de Mille railway epic Union Pacific, John Ford's skillful and dramatic Stagecoach, … and George Marshall's classic comic Western, Destry Rides Again. —Ira Konigsberg, The Complete Film Dictionary, 1987

  3. … new techniques of navigation and shipbuilding enlarged trade and the geographical horizon; newly centralized power absorbed from the declining medieval communes was at the disposal of the monarchies and the growing nationalism of the past century gave it impetus … —Barbara W. Tuchman, The March of Folly, 1984

  4. His discoveries have given impetus to further research.

  5. <the reward money should be sufficient impetus for someone to come forward with information about the robbery>

Origin of impetus

Latin, assault, impetus, from impetere to attack, from in- + petere to go to, seek — more at feather

First Known Use: 1641

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February 11, 2016

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